1. Field of the Invention
The present invention relates to a supporting device to vertically support a coupling rod of a central buffer coupling pivotably articulated vertically to a car body underframe of a vehicle by a bearing block, wherein the supporting device includes a support, able to be brought into contact with the coupling rod and a mount connected to the support which can be fixed to the car body underframe. The invention furthermore relates to the use of a supporting device in a railborne vehicle, in particular a rail vehicle.
2. Description of the Related Art
A supporting device of the above type is technically already known from the prior art, and in particular from rail vehicle technology. Such a supporting device serves to vertically support a coupling rod pivotably articulated vertically to a car body underframe.
FIG. 7 schematically depicts a partly sectional side view of a known per se central buffer coupling of AAR standard F (AAR=Association of American Railroads). The central buffer coupling 56 shown in FIG. 7 is particularly suited to connecting car bodies of a railborne vehicle, in particular rail vehicles, and includes thereto a coupling rod 50 with a coupling head 54 arranged at its coupling plane side end. As coupling head 54, the central buffer coupling 56 depicted in FIG. 7 specifically includes a coupling head of F classification in accordance with the AAR standard.
As can be gathered from FIG. 7, the coupling rod 50 is pivotably articulated via a bearing block 51 to the car body underframe 55 of the not explicitly shown, car body, in the vertical direction V and in the horizontal direction. In this way, the coupling rod 50 can follow the horizontal pivoting motion of coupling head 54 as well as vertical deflections, for example, to compensate for differences in height between the two coupling heads to be coupled together. The articulating of the coupling rod 50 ensues by an elastomer bearing configured in bearing block 51 in which elastomer spring elements 52 are provided, serving to cushion the tractive and impact forces transmitted from the coupling rod 50 in normal vehicle operation. Typically, the elastomer bearing configured in bearing block 51 is capable of allowing the coupling rod 50 the routinely required pivoting angle of approximately ±6° vertically and approximately ±15° horizontally.
The bearing block 51 is connected to a car body underframe 55 housing by a pivot pin 53. The housing of the car body underframe 55 also encloses a large part of the bearing block side section of coupling rod 50.
A supporting device 101 is provided in order to enable the appropriate vertical support for the coupling rod 50, articulated to pivot, vertically and otherwise. This type of vertical support is particularly necessary in order to enable trouble-free coupling of two central buffer couplings. In so doing, it needs to be ensured that the coupling rod 50 is always in the horizontal central longitudinal plane during the coupling procedure.
In the central buffer coupling 56 depicted schematically in FIG. 7, the supporting device 101 includes a support 102 configured as a support plunger which makes contact with the coupling rod 50. The supporting device 101, which is known per se, furthermore includes a mount 103. The supporting device 101 is an elastically-designed support in which the support plunger 102 is connected to the mount 103 by a spring element 104 and presses against the coupling rod 50 at a certain pretensioning as a result of the spring element 104. The pretensioning at which the support plunger 102 presses against the coupling rod 50 is adjustable by appropriately selecting the spring constant for the spring element 104 and should be selected such that in a non-operative state of the central buffer coupling 56; i.e., when no dynamic forces are being transmitted through the coupling rod 50 in the vertical direction V, the coupling rod 50 is in the horizontal central position.
The mount 103 of the supporting device 101, which on the one hand serves to hold the spring element 104 and the support plunger 102, and by which the support plunger 102 can be made to press against the coupling rod 50 supported at a certain pretensioning on the other, is rigidly connected to the car body underframe 55, respectively, the housing of car body underframe 55, by an attachment 105.
Arranging energy-absorbing devices in or on the underframe of rail vehicles is generally known in the field of rail vehicle technology. Normally employed as the primary stage, is a reversibly-designed energy-absorbing device, integrated in the form of a spring element in the coupling shaft, for example, and which is to cushion impact forces occurring during operating, maneuvering and coupling. It is also possible—as depicted in FIG. 7—to provide an appropriate drawgear in the bearing block of the articulation, for example, in the form of elastomer spring elements, by which the coupling rod is fixed to the underframe of the car body. These elastomer spring elements provided in the articulation cushion tractive and compressive forces within a defined limit and route forces in excess of same uncushioned to the vehicle underframe via the bearing block.
While this type of primary energy-absorbing device, designed, for example, as a reversible energy-absorbing device, at least partly cushions or absorbs those tractive and impact forces which occur between the individual car bodies of a multi-member vehicle during normal vehicle operation, when the working load of the primary energy-absorbing device is exceeded, for example, should the vehicle collide with an obstacle, the damping capacity provided by the primary stage is usually no longer sufficient to effectively prevent excessive impact force from being transmitted to the vehicle underframe. In such a case, the vehicle underframe is subjected to extreme loads such that the risk is run of the car body being damaged or derailing. The working load of the primary energy-absorbing device, also designated as the damping capacity provided by the primary stage, normally corresponds to the working load of the coupling itself.
One approach to preventing an uncushioned routing of impact forces to the vehicle underframe upon the working load of the primary energy-absorbing device being exceeded provides for, in addition to the primary stage, for example, in the form of elastomer spring elements in the articulation of the coupler shaft, a further (secondary) energy-absorbing device, for example, in the form of two side buffers at the outer edge of the front face of the respective car body. It is likewise known from rail vehicle technology to provide, additionally to or in place of side buffers as secondary energy-absorbing devices, at least one deformation tube downstream of the primary energy-absorbing device and which normally does not respond until after the working load of the primary energy-absorbing device, respectively coupling, is exceeded.
Regardless of its realization, the secondary energy-absorbing device serves to absorb or cushion the impact energy ensuing from excessive overrunning collisions. It is in principle also possible, after the primary energy-absorbing device has been exhausted, to deflect the remaining energy to energy-absorbing elements on the car body side, for example friction elements, by a predetermined breaking point in the coupler linkage.
The additional secondary energy-absorbing device provided, also called “overload protection,” thereby serves as an additional shock absorber to protect the vehicle underframe from damages in the event of strong rear-end collisions. As mentioned above, this type of secondary energy-absorbing device can, for example, be realized as side buffers at the outer edge of the front face of the car body. So that the secondary energy-absorbing device can, for example, in the event of a crash; i.e., upon exceeding the working load of the central buffer coupling, respectively the primary energy-absorbing device provided in the central buffer coupling, respond in a defined manner and dissipate or dampen excessive impact energy according to a pre-defined sequence of events, it is necessary for the coupling to be removed from the transmitted flow of force. This usually occurs in such a way that the coupling rod together with the coupling head disposed at the coupling plane side end of the coupling rod and the articulation provided at the car body side end of the coupling rod, are pushed backward toward the car body out of the coupling plane and thus, removed from the flow of force transmitted between two adjacent car bodies.
It is, for example, conceivable that after the energy absorption provided by the primary energy-absorbing device has been exhausted upon a critical impact force being exceeded, the articulation of the coupling rod, the bearing block respectively, shears off at predetermined breaking points and a substantial portion of the coupling is pushed into a space in the car body's underframe by a cross-member provided on the front face of the car body.
In the case of a central buffer coupling, on the other hand, which—as FIG. 7 depicts—exhibits a supporting device fixedly connected to the car body underframe for the vertical support of the coupling rod, in the event of a crash, the necessary longitudinal displacement of the coupling rod toward the car body is limited by the supporting device disposed on the car body underframe. Particularly in the case of couplings which exhibit relatively large displacement in the event of a crash, the supporting device fixedly connected to the car body underframe prevents the coupling rod and the coupling head disposed at the coupling plane side end of the coupling rod from being removed from the flow of force transmitted between two adjacent car bodies in a defined manner, such that neither is a defined response of a conceivably provided secondary energy-absorbing device possible, and energy cannot be absorbed in the conceivably provided secondary energy-absorbing device according to a predetermined sequence of events.